"If you can persuade one of the others to join you in your circle, or if you want to join the others in theirs, and three of you agree, point to the other and say, 'Mole, mole, go to your hole'. If they're wrong, they get evaporated."

Lesley Judd shrieks, Madeleine Smith says that she won't say anything, which is hardly different from the rest of the programme. David Yip queries the rules, and Derek Gale asks if there really was a mole, and says that this is where they start the accusations. Ganord says that the group has one minute, the lights go down to a spooky level, casting long shadows, and some dragons appear - in dragon form, no less - to intimidate the contestants. Viewed from a somewhat later point in history, we wonder if this little scene can claim to be a predecessor to the popular party game of Mafia, and if the short series Traitor (2004) was timed to air in the same 6pm slot. The timeslot is a coincidence, surely.

The dragons are out this evening

Back at the game, Lesley's wondering if there's a way of doing this, and the others are completely lost for words. The gentlemen, sharing a circle, are sure they're not the mole, which leaves one of the ladies. Lesley encourages the others to vote on it. David and Derek look convinced, and point out that Lesley's the obvious candidate, as she joined proceedings some time after the start. The gents eventually realise that Madeleine's done nothing of substance all show, and invite Lesley across.

Let the finger pointing begin

But then the finger-pointing starts: Madeleine accuses Derek of being "too clever by half", and Lesley joins in the accusations. With just a few seconds on the clock, and Lesley not moving, David leaps across to the other circle, where the remaining three shout, "Mole, mole, go to your hole!"

Does this look like the face of a mole?

Derek gets evaporated. The mole was Lesley, who promises, "You haven't seen the last of me yet!" That probably explains why she was seen at the start of the show reading that well-known spy journal the Daily Mole.

Moles in your garden: do they hurt house prices?

Ganord, being the fine upstanding citizen of Arg, insists that Lesley hands over the postcard she picked up in the kitchen. "Dear Argonauts, Do swim around for a better understanding. Yours, Dr Owssap." There's an edit at this point, and one of the team signs himself into the computer as "Daviod Yip". He has an increasingly esoteric conversation with the computer.

Ask a silly question...

Another edit sees us back in the kitchen, where the remaining adventurers have a key, saying "T for Time." Daviod suggests a nice hot cup of tea. "Milk?" he asks. "No, you must never have milk with Earl Gray tea," replies Madeleine. Patrick Dowling's recollection of this incident - that a dragon dressed as a milkman offered her the liquid - is sadly at variance with the facts.

The milk is an Argond's favourite: evaporated

Another edit sees us back in the main room, where the two are discussing with Ganord; clearly, they're beginning to run out of time before the studio hands call a halt to proceedings. Daviod types "wisdom" into the computer. Apple II computers aren't too familiar with earth languages, particularly when he's typed "wwisdom". "Wisdom" is the password, but it's too early - they've got to get the right time. "Time for T" says Madeleine.

W-W-I-S-D-O-M

Another edit, and Daviod's thumbing through the Book of Signals they found late last week. Is the semaphore picture on the wall of any use to them? Maybe: what if they put the semaphore signal for "T" on the clock. The face is locked, but the "Time for T" key opens it. The code is (roughly) 10 o'clock, the clock chimes, and then it quacks. The computer screen reads, "Please enter the password now".

Have they worked out what the signal is?

After a couple of false starts, Daviod finally enters "Wisdom", and is rewarded with a message. "Your flight is boarding now, departure in five minutes. Please have your drogna ready."

In semaphore, T is represented by 10 o'clock

We'll just pause here to consider the clues. Last week, the team received two postcards. The first read, "God give them wisdom that have it, and those that are fools, let them use their talents!" The second card spoke about "seven pillars", and it took a not very subtle hint from Ganord to lead them to the answer. And "Do swim" is an anagram, something they should put "around". There's no particular meaning in the picture of semaphore signs, merely that they are semaphore signs.

I'm not going to tell you the password is wisdom...

Back in the ticket office, Gandor is putting on his officious inspector's hat, and asking for the fares home. Fifteen drogna per person, then there's the fuel surcharge, spaceport tax, though not a Taking the Mickey tax; even dragons wouldn't think of charging visitors to advertise the brilliance of their planet. But rather than fill all these boxes, Gandor suggests a little back-hander, and takes their remaining drogna in exchange for pure glass crystals. Ganord convinces him to give them a crystal each for their time on the planet. And a ham sandwich for the trip.

Tickets, please

It's clear that Daviod and Madeleine never got to grips with the drogna markings. It really was very simple: the number of sides on the shape is multiplied by the colour on the rainbow. A red circle is valued at (1x1) one drogna, a red pentagon (1x5) and blue circle (5x1) have equal values, and the green square that Gandor had was worth 16.

Welcome to my vortex!

Out of the door, we see Lesley and Derek by a console. Derek's been evaporated here, and now has his chance to help Lesley exact revenge. If Madeleine or Daviod get evaporated, this high-powered state-of-the-arg evaporator will send them right off to the hyper-space lane. "Welcome to my Vortex," cries Lesley to the visitors, and Ganord gives a demonstration of how the game works. It's a little easier because she can see the evaporation beam.

Ganord dances past the evaporator beam

The rules of the vortex are very very simple. Even an aspidistra could understand them. Get from that side to this, along the paths, without walking into the evaporation beam, otherwise whoosh! There'll be no place on the shuttle.

Derek, Lesley, and Ganord use this controller to move the beam

Madeleine is first to tackle the challenge, and side-steps on her second move. Derek's playing a clever game, retreating to lure Madeleine into the corner, where she's evaporated. Daviod side-steps on his second move, advances to a middle corner, forcing the beam to his side, but then retreats! It's a foolish move, and (quite frankly) he deserves to be evaporated.

Madeleine steps into the beam

Lesley and Ganord adjust the scoreboard: counting evaporations from the previous series (Earth 7, Arg 8), it's now Earth 9, Arg 12. Ganord muses that it'll be a cold night, but someone will come along and give Madeleine and Daviod a lift. They're at a sign-post on the journey, and try to flag down the Arg shuttle.

Derek boards the shuttle home

It's not stopping. Long walk home!

Any chance of a lift?

The key credits for this series: Nick Moore made the video effects, spattering out from the middle of the screen as people were evaporated, or the Argonds shifted their shape. Dennis Collett had the thankless task of editing down hours of footage into a coherent 45-minute programme. Katherine Ayerst made the costumes, Mickey Edwards and Steve Bowman the special effects, Lynda Kettle and Bob Hutton the set design. The show was directed by Ian Oliver, and written and produced by Patrick Dowling.

The hidden message in the show's logo

The question we set in the Game Show Times was to explain: "A skateboard for a drumming granny; the sharp end of Lucifer; and the follower of the Rear of the Year 1986. Young Sherlock completes the set." The answer follows much later.

We would like to tell you who else appeared on this episode. Thanks to the unique way in which the BBC is funded, the information is under lock and key.

6.35 BBC2 The World Chess Championship

Bill Hartston and guests discuss the latest moves in Karpov's match against Korchnoi. After winning three of the first four games, Karpov found the overall victory more elusive than he might have hoped; going into this week's matches, his lead was 4-1, with the first to 6 winning the title.

Friday

Two married couples, a giant pack of cards, and the humour of Brucie. Tonight: the Fosters of Coventry, and the McBrides of Glenrothes.

This Week And Next

Back to the present day, by means of the recent past. Readers will, perhaps, remember Deal or No Deal, a simple guessing game presented by the simply awful wardrobe of Noel Edmonds. The show was last in the news for unfairness in its 0898 Legalised Telephone Lottery. Now, the host has claimed that he was never in favour of the call-and-lose contest, claiming that "it destroyed the atmosphere of the show and it didn't engage the public." This raises the question: why didn't he say so earlier?

Speaking of increasingly desperate gimmicks, the BBC has quietly snuck out a press release (in the middle of an Andy Murray match, no less). They're going to be making a very silly Saturday evening show, combining Dale Winton, leotards, a wall, and a swimming pool. Oh, and some minor celebrities. Next, surely, is the latest revival of Jeux Sans Frontieres.

In other news, Channel 4 has finally seen sense, and commissioned another daytime series of Come Dine with Me. It's set to go out in December, in the slot vacated by Richard and Judy after their show moves to satellite. Come Dine With Me will be paired with Total Recall, a show in which Terry Wogan invites contestants to remember answers from previous rounds, and they invite him to mind his manners and not call his hosts Dr. Death.

Ratings for the week to 22 June, and it's a great week for Beat the Star. The last show in the current run saw Vernon Kay beat his challenger, and beat all other game shows, with 5.2m viewers. Big Brother finished second, 3.8m were attracted to Thursday's show, and a repeat of The Weakest Link: Puppets was seen by 3.45m. Come Dine With Me finished its series just shy of 3m - like Beat the Star, it ends its run almost as popular as when it began.

Come Dine With Me was the most popular programme on digital channels, 635,000 tuning in on Sunday, just beating America's Got Talent on ITV2. Big Brother's Big Mouth on Wednesday came in third, with a series-best 495,000 seeing Wednesday's show. Never Mind the Buzzcocks had its highest audience of the year on Dave, Monday's episode was seen by 470,000. A good week for CBBC's Clutter Nutters, 185,000 for the Saturday lunchtime edition; a good week for Bullseye on Challenge, recording its first six-figure audience of the year.

The quiz answer. A skateboard for a drumming granny; the sharp end of Lucifer; and the follower of the Rear of the Year 1986. Young Sherlock completes the set. The drumming granny was the abiding image of Eurovision 2005, and came from Moldova, where they played tennis against comedian Tony Hawks (not skateboarder Tony Hawk). "Lucifer" is the Dutch word for "safety match", the sharp end of which is a Matchpoint, a short-lived tennis quiz. Rear of the Year 1986 was Anneka Rice, followed on Treasure Hunt by Annabel Croft, the last British winner of the Wimbledon girls singles before yesterday. And in the 1986 film, Young Sherlock was played by Nicholas Rowe, later to be The Questioner on Grand Slam. The link is tennis.